What SLPs Need to Know About APD LSHSS Sept 2010

8/3/2019 What SLPs Need to Know About APD LSHSS Sept 2010

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Abstract

Purpose: To consider whether APD is truly a distinct clinical entity or whether auditory

problems are more appropriately viewed as a processing deficit that may occur with

various developmental disorders.

Method: Theoretical and clinical factors associated with APD are critically evaluated.

Results: There are compelling theoretical and clinical reasons to question whether APD

is in fact a distinct clinical entity. Not only is there little evidence that auditory

perceptual impairments are a significant risk factor for language and academic

performance (e.g., Hazan et al., 2009; Watson & Kidd, 2009), there is also no evidencethat auditory interventions provided any unique benefit to auditory, language, or

academic outcomes (Fey et al., this issue).

Conclusion: Because there is no evidence that auditory interventions provide any unique

therapeutic benefit (Fey et al., this issue), clinicians should treat children diagnosed with

APD the same way they treat children diagnosed with language and learning disabilities.

The theoretical and clinical problems with APD should encourage clinicians to consider

viewing auditory deficits as a processing deficit that may occur with common

developmental language and reading disabilities rather than as a distinct clinical entity.


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Acquiring the language, conceptual knowledge, and reasoning skills necessary to

talk, understand, read, write, and reason well is challenging even for typical learners. For

students with language and learning disabilities, acquiring these skills may often appear

insurmountable to families, teachers, and the particular student. Given these challenges,

it is not surprising that families and teachers will be attracted to simple solutions to

language and learning problems. Interventions that target processing skills are

particularly appealing because they offer the promise of improving language and learning

deficits without having to directly target the specific knowledge and skills required to be

a proficient speaker, listener, reader, and writer.The Appeal and Controversy about Auditory Processing Disorders (APD)

One of the most appealing processing explanations for language and learning

disabilities is an impairment in the ability to process auditory information. Despite the

considerable controversy about the definition and diagnostic criteria for APD (cf. Cacace

& McFarland, 2009; DeBonis & Moncrieff, 2008), many believe that a comprehensive

management plan for children with this impairment should include interventions that

specifically target auditory perceptual skills (e.g., Bellis, 1996; Geffner & Swain-Ross,

2007). The systematic review conducted by our ASHA committee (Fey et al., this issue)

found no compelling evidence, however, that auditory interventions provided any unique

benefit to auditory, language, or academic outcomes for children with diagnoses of APD

or language disorder.

Although the findings from the systematic review were straightforward, several

members of the committee felt strongly that drawing any conclusions would be premature

because of the following limitations:


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1. Studies were not excluded based on how APD was defined, so the population of

children with APD may be too heterogeneous.

2. Objective instruments (e.g., electrophysiological procedures) were not used to

differentiate subgroups of APD.

3. There were a limited number of efficacy studies with large samples

4. Most of the studies used Fast ForWord or Fast ForWord-like acoustic

modifications.

5. Few studies included measures of long-term outcomes.

6. The effect of auditory interventions on children with learning disabilities was notconsidered.

To address these limitations and fill the gaps in our understanding, the committee

recommended that programs of thematically coherent research were needed. These

programs should begin with small-scaled rigorous studies with participants who are

carefully evaluated using a comprehensive battery of conventional tests of APD as well

as neurophysiological indices. A critical component of these studies is the adequate

identification of individuals with APD and APD subgroups with rigorous test batteries

that evaluate auditory skills as well as language abilities. Specific hypotheses developed

from these studies should then be tested in high quality efficacy and effectiveness studies.

The suggestions for future research may seem to be a logical and sensible way to

address the limitations in the current body of evidence, but any optimism that future

research will lead to consensus about the efficacy of auditory interventions needs to be

seriously tempered by the lack of agreement among audiologists about the definition and


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diagnostic criteria of APD. As Burkard wrote in his foreword to Cacace and

McFarlands (2009) recent book on APD,

There is currently great divisiveness in the field of audiology concerning CAPD.

There is no broadly accepted definition of CAPD. No one really knows what

causes CAPD. Despite lofty claims to the contrary, there is no clear consensus

concerning the battery of tests that lead to a diagnosis of CAPD. Similarly, there

is no widely accepted auditory (re)habilitation program that has been conclusively

shown to help those with CAPD. The strength and value of this book is that it

clearly points out that the emperor has no clothes. We are hamstrung by thelack of agreement and test batteries in the area of CAPD. (p. vii)

The contributors to the Cacace and McFarland book express very different

opinions about how these fundamental issues can be addressed. Reading these diverse

views leaves one with little hope that there will ever be consensus about the definition

and diagnostic criteria for APD. Jerger and Musiek (2000), for example, recommend that

behavioral measures should be supplemented with electrophysiological and

electroacoustic measures, whereas Katz and colleagues (Katz et al., 2002) argue that

there is no evidence that these additional measures are useful in identifying APD. Even

if there were a consensus among the audiology research community about an APD test

protocol, it is unlikely that clinical audiologists would uniformly use it. A survey of

audiologists APD diagnostic practices (Emmanuel, 2002) found that none were using a

protocol that met even the minimum guidelines recommended in the Consensus

Conference Report (Jerger & Musiek, 2000). Without consensus about the diagnostic


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criteria for APD, it is not possible to adequately identify APD and APD subgroups using

more rigorous test batteries. Adequate identification requires consensus.

If audiologists cannot agree about APD, where does that leave speech-language

pathologists (SLPs)? How are we supposed to make informed clinical decisions about

the treatment of children with suspected APD? Knowing the history of APD may help.

There are, in fact, three distinct views of APD that have jockeyed for prominence among

audiologists and SLPs. Knowledge of these discrepant views explains the current

controversies about the definition and diagnostic criteria for APD. After reviewing this

history and the difficulty defining APD, I consider the theoretical and clinical problemswith APD. These problems suggest that it may be more appropriate to view auditory

deficits as a characteristic of various developmental disorders rather than as a distinct

clinical entity. I conclude with a list of suggestions for SLPs who provide services to

children diagnosed with APD.

A Brief History of APD

The link between auditory processing impairments and speech, language, and

learning has a long history in our profession. Myklebust (1952) was one of the first to

note that some young children have disturbances of auditory perception without

symbolic language disorders (p. 157). It took more than 10 years for Myklebusts ideas

to become formalized in the widely popular Illinois Test of Psycholinguistic Abilities

(ITPA, Kirk, 1968). In the perceptual-motor domain, the ITPA had five auditory

subtests: auditory reception, auditory association, auditory sequential memory, auditory

closure, and sound blending. Poor performance on one or more of these subtests was

taken as evidence that the child had an auditory perceptual problem. These perceptual


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problems formed the foundation of the discrete-skill, psychoeduational view of

language development that influenced assessment and treatment of many children with

auditory processing disorders as well as those diagnosed as language impaired through

the 1960s and 1970s.

It was not until the mid-1980s that a distinct audiologic approach gained

momentum. The audiologic approach grew out of observations of early 20 th century

neurologists like Jackson and Head (cited in Jerger, 2009) that soldiers with known brain

injury to the auditory central nervous system exhibited certain auditory perceptual

problems. This led to the development of tests to assess auditory perception. If thesetests revealed perceptual problems, the patient was viewed as having a brain injury.

Although some investigators noted the circular reasoning in this diagnosis, others were

not bothered by the tautology and set out to create auditory perceptual tests that could be

administered to children (Jerger, 2009). The most popular tests developed were the

SCAN: Screening Test for Auditory Processing Disorders in Children (Keith, 1986,

2000), The Staggered Spondaic Word Test (SSW; Arnst & Katz, 1982), and the Pediatric

Speech Intelligibility test (Jerger, Jerger, & Abrams, 1983). Not coincidentally, these

tests represent the core assessment battery used to diagnose APD.

As the audiologic approach gained momentum, the discrete-skill,

psychoeducational approach fell out of favor in speech-language pathology. It was

replaced by linguistic, cognitive, and social interaction perspectives that focused attention

on language form, content, and use (e.g., Bloom & Lahey, 1978). Assessments and

interventions were developed to target each of these areas. The growing popularity of the

audiologic approach inevitably led to renewed interest in the psychoeducational model.


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Bellis (1996) uniquely combined the audiologic approach with the ITPAs five discrete

dimensions of auditory processing. The appeal of this combined approach persists today,

as exemplified by Geffner and Ross-Swains (2007) recent book on the assessment,

management, and treatment of APD.

The third path in the history of APD, or fourth if the combined approach is

viewed as a distinct path, is the language processing approach (Jerger, 2009).

Researchers and clinicians who study and treat children with language disorders view

auditory processing as only one component in the overall processing of language.

Conceptual and language knowledge obviously have an important role in languageprocessing. Jerger (2009) cites Medwetskys (2006) spoken language processing model

as an example of how to consider the intertwining effects of auditory processing,

cognition, and language. In his most recent work, Medwetsky (2009) presents a

comprehensive assessment battery that can be used to identify where breakdowns occur

in the processing of spoken language. Consistent with his model, Medwetsky prefers the

term Spoken Language Processing Disorder to characterize children who have deficits in

spoken language processing.

The significant differences in these views of APD help explain why there is no

broadly accepted definition for the disorder or clear consensus about diagnostic criteria

for APD. In the next section, I discuss some of the controversies surrounding the

definition and diagnosis of the disorder.

The Difficulty Defining and Diagnosing APD

The Working Group on Auditory Processing (ASHA, 2005) defined auditory

processing as the perceptual processing of auditory information in the central nervous


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system that includes the following abilities or skills: sound localization and lateralization,

auditory discrimination, auditory pattern recognition, temporal aspects of audition, and

auditory performance with degraded acoustic signals. Importantly, the Working Group

recognized that although abilities such as phonological awareness, attention to and

memory for auditory information, and auditory comprehension may be associated with

intact central auditory function, these abilities are higher order cognitive-communicative

and/or language-related functions that should not be included in the definition of APD

(ASHA, 2005, p. 2). Our ASHA Committee was in general agreement with this

definition because of this distinction.Unfortunately, definitions of disorders do not always coincide with the way they

are diagnosed. This is clearly the case for APD because the tests used to diagnose the

disorder are not pure measures of auditory abilities. To make auditory measures more

effective in identifying disorders in the central auditory system, they had to be

sensitized in some way. This was usually accomplished by increasing the complexity

or reducing the redundancy of the test stimuli. The consequence of sensitization,

however, made the measures susceptible to the influence of higher-level language and

cognitive abilities as well as memory and attentional factors (Cacace & McFarland, 1998;

Lum & Zarafa, in press). One cannot assume, then, that poor performance on an APD

test battery is caused by poor auditory abilities rather than some non-auditory factor. As

a case in point, a recent study by Lum and Zarafa (in press) found that when verbal

working memory was controlled, significant differences on the SCAN-C between

children with specific language impairment and age-matched controls disappeared

completely. This finding suggests that it is more appropriate to view difficulties on the


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SCAN-C as a problem with verbal working memory than auditory processing. The same

could probably be said for other commonly used tests used to diagnose APD.

To address the inconsistency between the definition and diagnosis of APD,

Cacace and McFarland (1998) and others (e.g., Cowan, Rosen, & Moore, 2009) have

argued that the diagnosis of APD should be applied only when a processing deficit is

demonstrated on a battery of auditory tasks. In their view, a deficit in auditory

processing only makes sense if one can rule out the influence of language knowledge,

basic cognitive processes like attention and memory, and other possibilities for poor

performance, such as fatigue, anxiety, or lack of motivation (McFarland & Cacace,2009). At minimum, the diagnosis of an APD would require that children perform poorly

on a battery of auditory tasks, but demonstrate age-appropriate performance on

comparable visual tasks (McFarland & Cacace, 2009). Poor performance on both

auditory and visual tasks would indicate a non-modality specific deficit.

Not surprisingly, McFarland and Cacaces views are quite controversial in the

audiology community. The Working Group on Auditory Processing (ASHA, 2005), for

example, argued that the modality specific view was implausible because basic

cognitive neuroscience has shown that there are few, if any, entirely compartmentalized

areas in the brain that are solely responsible for a single modality (p. 3). This reasoning

seems puzzling. If basic neuroscience indicates that single modality processes cannot be

identified, why did the Working Group define APD as perceptual processing of only

auditory information?

Dawes and Bishop (2009) have a different view of the controversy over modality

specificity. They suggest that it stems from the lack of recognition of the different


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purposes associated with defining and diagnosing a disorder. They note that a narrow

definition that restricts APD to auditory deficits is necessary to understand causal

mechanisms. If one wants to understand the effect auditory deficits have on language or

reading, auditory measures cannot be confounded by non-auditory factors. In a clinical

setting, however, it makes little sense for audiologists to restrict the diagnosis of APD to

pure cases of an auditory deficit because most children referred for an APD evaluation

will have some associated listening and learning problem. If they did not have listening

or learning problems, they would not have been referred for APD testing. The diagnosis

of APD remains problematic, however, because it is often interpreted to mean thatauditory deficits are the primary cause of listening and learning problems.

One way to reconcile the conflicting views about modality specificity and the

different purposes of defining and diagnosing APD is to recognize that both researchers

and clinicians would benefit from the development of reliable and well-standardized

auditory measures that are not confounded by non-auditory factors. Researchers would

be better able to investigate causal mechanisms and clinicians would be able to determine

the relative impact of auditory and non-auditory factors on language and academic

performance. Moore and his colleagues have been developing such measures in England

(Moore, 2006). In their most recent study, they found that poor performance on auditory

tasks is due primarily to the attentional and memory demands of the tasks rather than

sensory challenges (Moore, Ferguson, Edmondson-Jones, Ratib, & Riley, in press).

Is APD a Distinct Clinical Entity?

As mentioned previously, there is still no consensus about how to diagnosis APD

among the audiology community. Even the so-called Consensus Conference Report


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(Jerger & Musiek, 2000) lacks consensus, as evidenced by this comment from Burkard in

his review of the initial draft of this article: I take umbrage at the use of the term

consensus, unless they specifically mean a consensus of those who were invited and

ultimately attended this meeting. The title of this conference and the resulting

publication overstates their case by the inclusion of the term consensus (Burkard, n.d.).

Given the lack of consensus about how to diagnose of APD, it should not be surprising

that there is still some question about whether APD is truly a distinct clinical entity (e.g.,

Cacace & McFarland, 2009; Dawes & Bishop, 2009). The alternative is to view auditory

processing problems as one of a number of deficits commonly found in developmentaldisorders (Dawes & Bishop, 2009). For example, many children with language and

learning difficulties have working memory deficits (Leonard, Ellis Weismer, Miller,

Francis, Tomblin, & Kail, 2007). The significant theoretical and clinical problems with

APD should at least make one consider the viability of the alternative view rather than

simply assuming that APD is truly a distinct clinical entity. I briefly discuss some of

these problems below. (For more comprehensive reviews, see recent articles by Dawes

and Bishop, 2009, Moore, 2006, and various chapters in Cacace and McFarland, 2009).

The clinical entity of APD is based in large part on the assumption that auditory

deficits are a primary cause of speech, language, and academic learning difficulties.

There is, however, a growing body of evidence showing that auditory perceptual deficits

are not a significant risk factor for speech and language develop

pment or later academic achievement (Hazan et al., 2009; Ramus, White, & Frith,

2006; Rosen, 2003; Watson, Kidd, Horner et al., 2003; Watson & Kidd, 2009). Watson


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et al. (2003), for example, found that measures of auditory processing had no impact on

reading or language abilities in grades 1 through 4, in a large sample of children

representative of national norms in intelligence and socioeconomic status. More recently,

Sharma et al. (2009) found that having auditory processing difficulties did not increase

the likelihood that a child would have a language or reading disorder. There is also now

considerable evidence that despite poor phonological processing abilities, individuals

with dyslexia perform within normal limits on measures of speech perception (Hazan et

al., 2009; Ramus, White, & Frith, 2006). Even researchers who believe in the possible

existence of APD acknowledge that the importance of auditory processing is underminedby these recent studies (e.g., Cowan et al., 2009).

The lack of consensus in diagnosing APD is, of course, a significant theoretical

and clinical problem. McFarland and Cacace (2006) argue that a disorder should not be

defined in terms of whatever a test measures (McFarland & Cacace, 2006). A disorder or

distinct clinical category should be defined by a deficit in a particular perceptual or

cognitive mechanism or function. Auditory deficits can occur at several different levels

(Medwetsky, 2009; Moore, 2006), so it is not sufficient simply to say that auditory

deficits cause APD. A strong genetic influence on the etiology of APD would provide

strong evidence that it is in fact a distinct clinical category. To date, however, the only

study that addressed this question found that auditory problems appeared to be caused

entirely by environmental factors (Bishop, Bishop, Bright, James, Delaney, & Tallal,

1999).

Concerns about the reliability and validity of APD tests are the most significant

clinical problem with APD (Cacace & McFarland, 2009; Dawes & Bishop, 2009). Even


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if a test is reliable and well-standardized, the test is often not a valid measure of auditory

abilities because of the influence of non-auditory factors on test performance. Another

significant clinical problem with APD is the lack of evidence that auditory interventions

provide any unique benefit to auditory, language, or academic outcomes (Fey et al., this

issue). The high comorbidity of APD with other developmental disorders (e.g., attention

deficit disorder, specific language impairment, and dyslexia) is also problematic (Cacace

& McFarland, 2006; Sharma, Purdy, & Kelly, 2009). High co-morbidity likely reflects

the influence of attention, memory, and language abilities on APD tests and thus would

be predicted by the view that auditory deficits are a common characteristic of developmental disorders. Importantly, the high co-morbidity of APD with other

developmental disorders cannot be taken as evidence that auditory deficits are the

primary cause of these disorders.

It should be clear that there are compelling theoretical and clinical reasons to

question whether APD is in fact a distinct clinical entity. At the present time, it seems

more appropriate to view auditory deficits as a processing deficit that may occur with

common developmental language and reading disabilities rather than as a distinct clinical

entity. Interestingly, Dawes and Bishop (2009) also suggest this possibility, but do so

after concluding that there is both clinical and theoretical support for the category of

APD (p. 459). On the following page, they suggest that it may be more helpful to

clinicians and researchers as well as the children and families concerned to consider

auditory processing problems as one of several dimensions of impairment associated with

a range of developmental conditions, rather than being a categorical disorder in its own

right (p. 460). The fact that they raise this possibility after concluding that there is


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support for the distinct category of APD is telling: Even researchers who want to believe

that APD is a distinct clinical category recognize that the current evidence for APD is not

convincing.

Why Only Three Processing Limitations Became Distinct Clinical Entities

With all of the possible candidates for processing disorders, it seems appropriate

to question why only three processing deficits became distinct clinical entities: APD,

Attention Deficit-Hyperactivity Disorder (ADHD), and Sensory Integration Disorder

(SID). Processing limitations that directly influence language and reading would seem

to be the most likely candidates to become distinct clinical entities, but this is not thecase. The processing abilities that affect language the most are working memory and

speed of processing. Limitations in these abilities have been found to account for 62% of

the variance in composite language scores of children with language impairments

(Leonard, Ellis Weismer, Miller, Francis, Tomblin, & Kail, 2007). The processing

abilities with the greatest influence on learning to read are phonological memory,

phonological awareness, and rapid serial naming. Deficits in these phonological

processes account for a large proportion of the variance in word recognition ability

(Wagner & Torgesen, 1987; Wagner, Torgesen, & Rashotte, 1994).

Despite the significant impact working memory, speed of processing, and

phonological processing have on language and reading, there has never been any attempt

to turn them into distinct clinical categories. Its a good thing, too. If all processing

deficits were distinct clinical categories, the list of disorders would be interminable. In

addition to a Working Memory Disorder, Speed of Processing Disorder, and a

Phonological Processing Disorder, we also could have a Phonological Memory Disorder,


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Rapid Serial Naming Disorder, Word Retrieval Disorder, and all of the possible language

processing disorders such as a Syntactic Processing Disorder, Morphological Processing

Disorder, Semantic Processing Disorder, and Pragmatic Processing Disorder.

So, why did attentional, auditory, and sensory integration problems become

distinct clinical entities? A number of factors contributed to the creation of these distinct

clinical entities, but the following three factors were particularly important: (a) Each

disorder is associated with a distinct profession and practitioner (audiologist,

psychologist, occupational therapist); (b) a certified, licensed professional in the

discipline is the only one qualified to administer the assessment battery and make thediagnosis; and (c) the label for the disorder is not stigmatizing and is easy to understand,

remember, and communicate to others (i.e., a good meme; cf. Kamhi, 2004). APD,

ADHD, and SID meet all of these criteria whereas none of the other processing

limitations do. A Working Memory Disorder and Phonological Processing Disorder fall

short on all three criteria. For example, although working memory and phonological

processing abilities can be assessed by a variety of practitioners with tests that anyone

can purchase (e.g., Comprehensive Test of Phonological Processing; Wagner, Torgesen,

& Rashotte 1999), the constructs they represent are difficult to understand and

communicate to others. Working memory and phonological processing will thus never

become distinct clinical entities that compete with existing disorders like specific

language impairment and dyslexia.

Summary and Conclusions

Simply put, enough is enough already! We have already expended far too much

time, energy, and resources trying to understand and treat a disorder that has not only


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defied definition, but lacks clear diagnostic criteria. Even if there were a consensus about

the definition of APD and the specific diagnostic criteria that characterize the disorder,

there is no compelling evidence that auditory deficits are a significant risk factor for

language or academic performance (e.g., Hazan et al., 2009; Watson & Kidd, 2009).

There is also no evidence that auditory interventions provided any unique benefit to

auditory, language, or academic outcomes (Fey et al., this issue). These theoretical and

clinical problems with APD suggest that it may be more appropriate to view auditory

deficits as a processing deficit that may occur with common developmental disorders

(e.g., SLI, dyslexia, ADHD) rather than as a distinct clinical entity. This does not changethe fact that SLPs will continue to have children on their caseloads diagnosed with APD,

so here are some suggestions for providing services to these children.

1. Dont assume that a child diagnosed with APD needs to be treated any

differently than children diagnosed with language and learning

disabilities.

2. A child diagnosed with APD does not need auditory interventions. Our

systematic review found no evidence that auditory interventions

provided any unique benefit to auditory, language, or academic

outcomes (Fey et al., this issue). Language interventions are just as

effective as auditory interventions in improving auditory abilities

(Gillam et al., 2008)

3. Perform a comprehensive assessment of speech, language, and literacy

abilities just like you would do with any other student who was referred

for an evaluation.


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4. Consider non-auditory reasons for listening and comprehension

difficulties, such as limitations in working memory, attention,

motivation, language and conceptual knowledge, and inferencing

abilities.

5. Target speech, language, literacy, and knowledge-based goals in

therapy.

6. Avoid goals that target processing skills like auditory discrimination,

auditory sequencing, phonological memory, working memory, or rapid

serial naming. There is no compelling evidence that targeting theseskills significantly improves language or reading ability (Fey et al., this

issue; Fletcher, 2007).

7. Recognize that acquiring the language, conceptual knowledge, and

reasoning skills necessary to talk, understand, read, write, and reason

well is challenging even for typical learners. Learning these skills will,

therefore, be particularly challenging for students with language and

learning disabilities.

8. Keep searching for more effective and efficient ways to improve

language and reading abilities, but be wary of interventions that

promise quick fixes.

9. Most important of all: Devote most of your time and effort teaching

students the knowledge and skills that will help them talk, understand,

read, write, and reason better.


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References

American Speech-Language-Hearing Association. (2005). (Central) auditory processing

disorders: The role of the audiologist [Position Statement]. Available at

http://www.asha.org/members/deskref-journals/deskref/default.

Arnst, D., & Katz, J. (Eds.). (1982). Central Auditory Assessment: The SSW Test. San

Diego, CA: College-Hill Press.

Bellis, T. (1996). Assessment and management of central auditory processing disorders

in the educational setting: From science to practice . San Diego, CA: Singular.

Bloom, L., & Lahey, M. (1978). Language development and language disorders. NewYork: Wiley.

Bishop, D., Bishop, S., Bright, P., James, C., Delaney, T., & Tallal, P. (1999). Different

origin of auditory and phonological processing problems in children with

language impairment: Evidence from a twin study. Journal of Speech, Language,

and Hearing Research, 42, 155-168.

Burkard, R. (2009). Foreword. In A. Cacace & D. McFarland (Eds.), Controversies in

central auditory processing disorder (pp. vii-viii). San Diego, CA: Plural.

Cacace, A., & McFarland, D. (1998). Central auditory processing disorder in school-aged

children: A critical review. Journal of Speech, Language, and Hearing Research ,

51 , 344-373.

Cacace, A., & McFarland, D. (2006). Delineating auditory processing disorder (APD)

and attention deficit hyperactivity disorder (ADHD): A conceptual, theoretical,

and practical framework. In T. Parthasarathy (Ed.), An introduction to auditory

processing disorders in children (pp. 39-61). Mahwah, NJ: Erlbaum.


20/25

20

Cacace, A., & McFarland, D. (2009). Controversies in central auditory processing

disorder . San Diego, CA: Plural.

Cowan, J., Rosen, S., & Moore, D. (2009). Putting the auditory processing back into

auditory processing disorder in children. In A. Cacace & D. McFarland (Eds.),

Controversies in central auditory processing disorder (pp. 187-198) . San Diego,

CA: Plural.

Dawes, P., & Bishop, D. (2009). Auditiory processing disorder in relation to

developmental disorders of language, communication and attention: A review and

critique. International Journal of Language and Communication Disorders, 44,440-465.

DeBonis, D., & Moncrieff, D. (2008). Auditory processing disorders: An update for

speech-language pathologists. American Journal of Speech-Language

Pathology, 17 , 4-18.

Emmanuel, D. (2002). The auditory processing battery: Survey of common practices.

Journal of the American Academy of Audiology, 13 , 93-117.

Fey, M., Richard, G., Geffner, D., Kamhi, A., Medwetsky, L., Paul, D., et al. (this issue).

Auditory processing disorders and auditory/language interventions: A

systematic review. Language, Speech and Hearing Services in Schools .

Fletcher, J. (2007, November). Why RTI: Enhancing outcomes for all students.

Miniseminar presented at the Annual Convention of the American Speech-

Language-Hearing Association, Boston, MA.

Geffner, D., & Ross-Swain, D. (2007). Auditory processing disorders: Assessment,

management and treatment. San Diego, CA: Plural.


21/25

21

Gillam, R., Loeb, D., Hoffman, L., Bohman, T., Champlin, C., Thibodeau, L., et al.

(2008). The efficacy of Fast ForWord language intervention in school-age

children with language impairment: A randomized controlled trial. Journal of

Speech, Language, and Hearing Research, 51, 97-120.

Hazan, V., Messaoud-Galusi, S., Rosen, S., Nouwens, S., & Shakespeare, B. (2009).

Speech perception abilities of adults with dyslexia: Is there any evidence for a

true deficit? Journal of Speech, Language, and Hearing Research, 52 , 1510-

1529.

Jerger, J. (2009). The concept of auditory processing disorder: A brief history. In A.Cacace & D. McFarland (Eds.), Controversies in central auditory processing

disorder (pp. 1-14) . San Diego, CA: Plural.

Jerger, J., & Musiek, F. (2000). Report of the Consensus Conference on the diagnosis of

auditory processing disorders in school aged children. Journal of the

American Academy of Audiology, 11 , 467-474.

Jerger, S., Jerger, J., & Abrams, S. (1983). Speech audiometry in the young child. Ear

and Hearing , 4, 56-66.

Kamhi, A. (2004). A memes eye view of speech-language pathology. Language,

Speech, and Hearing Services in Schools, 35, 105-111.

Katz, J., DeConde-Johnson, C., Brander, S., Delagrange, T., Ferre, J., King, J., et al.

(2002). Clinical and research concerns regarding the 2000 auditory processing

disorders Consensus report and recommendations. Audiology Today, 14 , 14-17.

Keith, R. (1986). SCAN: Screening Test for Auditory Processing Disorders in Children .

San Antonio, TX: Psychological Corporation.


22/25

22

Keith, R. (2000). SCAN-C: Test of Auditory Processing Disorders in Children-Revised.

San Antonio, TX: Psychological Corporation.

Kirk, S. (1968). Illinois Test of Psycholinguistic Abilities: Its origin and implications. In

J. Helmuth (Ed.), Learning disorders : Vol. 3 (pp. X-X). Seattle, WA: Special

Child Publications.

Leonard, L., Ellis Weismer, S., Miller, C., Francis, D., Tomblin, B., & Kail, R. (2007).

Speed of processing, working memory, and language impairment in children.

Journal of Speech, Language, and Hearing Research, 50 , 408-428.

Lum, J., & Zarafa, M. (in press). Relationship between verbal working memory and theSCAN-C in children with specific language impairment. Language, Speech, and

Hearing Services in Schools

McFarland, D., & Cacace, A. (2006). Current controversies in CAPD: From Procrustes

bed to Pandoras box. In T. Parthasarathy (Ed.), An introduction to auditory

processing disorders in children (pp. 247-263). Mahwah, NJ: Erlbaum.

McFarland, D., & Cacace, A. (2009). Models of central auditory processing abilities and

disorders. In A. Cacace, & D. McFarland (Eds.), Controversies in central

auditory processing disorder (pp. 93-108) . San Diego, CA: Plural.

Medwetsky, L. (2006, June 13). Spoken language processing: A convergent approach to

conceptualizing (central) auditory processing. The ASHA Leader, 11 , 30-31.

Medwetsky, L. (2009). Mechanisms underlying central auditory processing. In J. Katz

(Ed.), Handbook of clinical audiology (6 th ed.)(pp. 584-610). Philadelphia:

Lippincott, Williams & Wilkins.


23/25

23

Moore, D. (2006). Auditory processing disorder (APD): Definition, diagnosis, neural

basis, and intervention. Audiological Medicine, 4, 4-11.

Moore, D., Ferguson, M., & Edmondson-Jones, A., Ratib, S., & Riley, A. (in press). The

nature of auditory processing disorder in children. Pediatrics.

Myklebust, H. (1954). Auditory disorders in children . New York: Grune & Stratton.

Nittrouer, S. (2002). From ear to cortex: A perspective on what clinicians need to

understand about speech perception and language processing. Language,

Speech, and Hearing Services in Schools, 33, 237-253.

Pinker, S. (1994). The language instinct: How the mind creates language. New York:Morrow.

Ramus, F., White, S., & Frith, U. (2006). Weighing the evidence between competing

theories of dyslexia. Developmental Science, 9, 265-169.

Roberts, J., Hunter, L., Gravel, J., Rosenfield, R., Berman, S., Haggard, M., et al. (2004).

Otitis media, hearing loss, and language learning: Controversies and current

research. Journal of Developmental and Behavioral Pediatrics, 25 , 110-122.

Rosen, S. (2003). Auditory processing in dyslexia and specific language impairment: Is

there a deficit? What is its nature? Does it explain anything? Journal of Phonetics,

31 , 509-527.

Sharma, M., Purdy, S. C., & Kelly, A. S. (2009). Comorbidity of auditory processing,

language, and reading disorders. Journal of Speech, Language, and Hearing

Research, 52 , 706722.

Wagner, R., & Torgesen, J. (1987). The nature of phonological processing and its causal

role in the acquisition of reading skills. Psychological Bulletin, 101 , 1-21.


24/25

24

Wagner, R., Torgesen, J., & Rashotte, C. (1994). Development of reading-related

phonological processing abilities: New evidence of bidirectional causality from a

latent variable longitudinal study. Developmental Psychology, 30 , 73-87.

Wagner, R., Torgesen, J., & Rashotte, C. (1999). Comprehensive Test of Phonological

Processing. San Antonio, TX: Pearson.

Watson, C., Kidd, G., Horner, D., Connell, P., Lowther, A., Eddins, D., et al. (2003).

Sensory, cognitive, and linguistic factors in the early academic performance of

elementary school children: The Benton-IU Project. Journal of Learning

Disabilities, 36, 165-197.Watson, C., & Kidd, G. (2009). Associations between auditory abilities, reading, and

other language skills in children and adults. In A. Cacace, & D. McFarland

(Eds.), Controversies in central auditory processing disorder (pp. 218-242) . San

Diego, CA: Plural.


25/25

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Acknowledgments

I would like to thank the members of ASHA committee for their help in refining my ideas

about APD. I would also like to acknowledge the helpful comments of the two

reviewers, Bob Burkard and David Moore, as well as Mary Kristen Clark who provided

helpful comments on all of the previous drafts and Hugh Catts for always being a

sounding board for my ideas. Finally, I would like to thank the graduate students in my

Spring, 2010 school-age language class, particularly Mike Maykish, for their probing

questions that pushed me to fully embrace the view that APD is best viewed as a

processing deficit that may occur with various developmental disorders.

Documents

What SLPs Need to Know About APD LSHSS Sept 2010